Ultrahigh-Field MR-Compatible Mechanical Tactile Stimulator for Investigating Somatosensory Processing in...

Area of Science:

• Neuroscience
• Primate Research
• Biomedical Engineering

Background:

• Common marmosets are valuable models for human sensory processing due to shared pathways.
• Functional magnetic resonance imaging (fMRI) in small primates is challenging due to stimulation delivery issues in strong magnetic fields.
• Ultrahigh-field (UHF) MRI enables high-resolution brain imaging in small animals.

Purpose of the Study:

• To develop and validate an MR-compatible tactile dual-point stimulator for precise mechanical stimulation in small-bodied animals.
• To explore somatosensory processing in common marmosets using functional MRI.
• To assess the device's performance and MR compatibility.

Main Methods:

• Development of an MR-compatible tactile dual-point stimulator.
• Testing device output with a pressure sensor and MR compatibility using a water phantom (tSNR).
• Conducting block-designed tactile stimulation experiments on three male common marmosets using 7T fMRI (CBV-weighted GE-EPI sequence).

Main Results:

• The stimulator delivered mechanical stimulation with an average force of 31.69g and a 12ms delay.
• Phantom experiments showed no significant difference in temporal signal-to-noise ratio (tSNR) across stimulation conditions (p=0.49).
• fMRI data revealed successful elicitation of hand and forearm somatosensory activations in primary somatosensory areas.

Conclusions:

• The developed MR-compatible tactile stimulator is effective for precise somatosensory stimulation in small animals.
• The device is suitable for high-resolution fMRI studies of somatosensation in common marmosets.
• This technology advances the study of sensory processing in non-human primates.